a. Field of the Invention
The present invention relates generally to floor mouldings, and, more particularly, to a moulding strip which has an interlocking construction and which is adjustable in height so that it can be used along the edges having floor coverings of different thicknesses/heights.
b. Background
Elongate transition mouldings are commonly installed along the edges of floor surfaces where there is a transition to another type of floor covering or to an area in which the subfloor is exposed. For example, such mouldings are commonly installed between carpet and laminate/linoleum/tile floor coverings, and at transitions where a covered floor surface ends and drops down to an area in which the underlying concrete or wood subfloor is exposed. Oftentimes, the edge is curved, so that the moulding must be flexible in order to follow the contours of the transition.
One such type of moulding (e.g., snap-in, track-base mouldings available from Johnsonite, Chagrin Falls, Ohio) uses a two-piece interlocking construction in which there is a base member forming a channel which is mounted to the subfloor, and a cap strip having a depending wall portion which is received in the channel. After the carpet or other floor surface material has been laid over the base strip, the lower edge of the cap strip is pressed into the channel to lock the two members together.
A particular deficiency which is exhibited by conventional mouldings of this type is that the assembly defines a fixed vertical height between the subfloor and cap for any given size of moulding. This is a serious drawback, because floor coverings of different thicknesses are often installed in various areas of the same structure. For example, the height of the flooring surface may only be ¼″ above the subfloor in some areas, and in other areas (such as along the edges of tiled surfaces) the height of the floor surface may be ½″ or more above that of the subfloor.
Consequently, since no single size of the conventional interlocking moulding material can accommodate these variations in height, it is necessary for the installer to have two or more different sizes of the material constantly available, at added cost and inconvenience. Moreover, the need to provide several different heights of cap strips adds significantly to the manufacturer's and supplier's costs.
Some attempt has been made to address this problem by providing an auxiliary channel strip which mounts within the first so as to raise the overall height of the assembly. However, since this requires the installer to buy and assemble yet another piece of material, and because each size of “add-on” channel has its own fixed height, this does little or nothing to alleviate the problems of cost and inefficiency which are inherent in the conventional product.
Accordingly, there exists a need for a transition moulding in which a single size of moulding can be utilized in installations requiring different heights according to the thicknesses of the adjoining floor coverings. Furthermore, there exists a need for such a transition moulding that can be used in conjunction with standardized mounting hardware that is readily available on the market. Still further, there exists a need for such a transition moulding that can be installed quickly and without requiring the use of specialized tools. Still further, there exists a need for such a moulding that is sufficiently flexible to allow installation along curved contours, but which is sufficiently stable once installed to avoid undesirable shifting or displacement underfoot during use. Still further, there exists a need for such a transition moulding that is durable and presents an attractive appearance, and which is also economical to manufacture.